-LRB- CNN -RRB- -- The state of New Jersey is imposing harsher restrictions on Ferris wheel safety after an 11-year-old rider fell to her death earlier this month .

Officials are mandating riders be at least 54 inches to ride without supervision , according to a letter from Michael Triplett of the New Jersey Carnival and Amusement Ride Safety Unit .

Triplett also `` strongly recommended '' that each car have at least two riders , and added that if a manufacturer has a more strict requirement , that requirement should be followed .

The changes coincide with the release of a preliminary report into the death of Abiah Jones of Pleasantville , New Jersey , who fell at Morey 's Piers Mariner 's Landing Pier , in Wildwood , on June 3 .

Jones , who met a 54-inch height requirement , was on a school trip when she fell from one of the park 's main attractions , called The Great Wheel . After receiving first aid at the scene , she was taken to Cape Regional Medical Center , where she was pronounced dead .

How the girl fell is still undetermined , and officials have no eyewitnesses , according to a report by the state of New Jersey . Surveillance footage showed her during the fall but did not show her leaving the gondola , the report said .

It determined she entered the ride as a single rider and sustained `` significant head trauma as well as cuts on her arms and shoulders , '' hitting several objects on her way to the ground .

The findings also concluded operators had no knowledge of any problems , the ride had no mechanical defects , and no other problems had been reported in its 25-year history .

`` The fact that Abiah Jones was alone in the gondola , without any nearby passengers , may have led her to take a risk that she would have been convinced not to take if there were other riders in the gondola , '' the state investigator concluded .

At 156 feet , the ride is one of the tallest wheels on the East Coast , Morey Piers spokeswoman Lindsey Young told CNN .

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Riders must be 54 inches tall to ride without supervision , new rules mandate

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Having two riders in each car is `` strongly recommended , '' official 's letter states

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Abiah Jones , 11 , fell to her death at a Wildwood amusement park on June 3

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How the girl fell has not been determined ; officials have no eyewitnesses